Manser Renee, Dalton Andrew, Carter Rob, Byrnes Graham, Elwood Mark, Campbell Donald A
Clinical Epidemiology and Health Service Evaluation Unit, Ground Floor Charles Connibere Building, Royal Melbourne Hospital, Grattan Street, Parkville, Vic. 3050, Australia.
Lung Cancer. 2005 May;48(2):171-85. doi: 10.1016/j.lungcan.2004.11.001. Epub 2005 Jan 4.
Low dose spiral computed tomography (CT) is a sensitive screening tool for lung cancer that is currently being evaluated in both non-randomised studies and randomised controlled trials.
We conducted a quantitative decision analysis using a Markov model to determine whether, in the Australian setting, offering spiral CT screening for lung cancer to high risk individuals would be cost-effective compared with current practice. This exploratory analysis was undertaken predominantly from the perspective of the government as third-party funder. In the base-case analysis, the costs and health outcomes (life-years saved and quality-adjusted life years) were calculated in a hypothetical cohort of 10,000 male current smokers for two alternatives: (1) screen for lung cancer with annual CT for 5 years starting at age 60 year and treat those diagnosed with cancer or (2) no screening and treat only those who present with symptomatic cancer.
For male smokers aged 60-64 years, with an annual incidence of lung cancer of 552 per 100,000, the incremental cost-effectiveness ratio was 57,325 dollars per life-year saved and 105,090 dollars per QALY saved. For females aged 60-64 years with the same annual incidence of lung cancer, the cost-effectiveness ratio was 51,001 dollars per life-year saved and 88,583 dollars per QALY saved. The model was used to examine the relationship between efficacy in terms of the expected reduction in lung cancer mortality at 7 years and cost-effectiveness. In the base-case analysis lung cancer mortality was reduced by 27% and all cause mortality by 2.1%. Changes in the estimated proportion of stage I cancers detected by screening had the greatest impact on the efficacy of the intervention and the cost-effectiveness. The results were also sensitive to assumptions about the test performance characteristics of CT scanning, the proportion of lung cancer cases overdiagnosed by screening, intervention rates for benign disease, the discount rate, the cost of CT, the quality of life in individuals with early stage screen-detected cancer and disutility associated with false positive diagnoses. Given current knowledge and practice, even under favourable assumptions, reductions in lung cancer mortality of less than 20% are unlikely to be cost-effective, using a value of 50,000 dollars per life-year saved as the threshold to define a "cost-effective" intervention.
The most feasible scenario under which CT screening for lung cancer could be cost-effective would be if very high-risk individuals are targeted and screening is either highly effective or CT screening costs fall substantially.
低剂量螺旋计算机断层扫描（CT）是一种用于肺癌的敏感筛查工具，目前正在非随机研究和随机对照试验中进行评估。
我们使用马尔可夫模型进行了定量决策分析，以确定在澳大利亚的情况下，与当前做法相比，为高危个体提供肺癌螺旋CT筛查是否具有成本效益。这项探索性分析主要是从作为第三方资助者的政府角度进行的。在基础案例分析中，计算了一个假设的10000名男性现吸烟者队列中两种方案的成本和健康结果（挽救的生命年数和质量调整生命年数）：（1）从60岁开始每年进行CT筛查肺癌，持续5年，并治疗那些被诊断患有癌症的人；（2）不进行筛查，仅治疗那些出现症状性癌症的人。
对于年龄在60 - 64岁的男性吸烟者，肺癌年发病率为每10万人552例，每挽救一个生命年的增量成本效益比为57325美元，每挽救一个质量调整生命年的增量成本效益比为105090美元。对于年龄在60 - 64岁、肺癌年发病率相同的女性，每挽救一个生命年的成本效益比为51001美元，每挽救一个质量调整生命年的成本效益比为88583美元。该模型用于研究在7年时肺癌死亡率预期降低方面的疗效与成本效益之间的关系。在基础案例分析中，肺癌死亡率降低了27%，全因死亡率降低了2.1%。筛查检测到的I期癌症估计比例的变化对干预效果和成本效益影响最大。结果还对关于CT扫描的检测性能特征、筛查过度诊断的肺癌病例比例、良性疾病的干预率、贴现率、CT成本、早期筛查发现癌症个体的生活质量以及与假阳性诊断相关的负效用等假设敏感。根据目前的知识和实践，即使在有利的假设下，以每挽救一个生命年50000美元作为定义“成本效益”干预的阈值，肺癌死亡率降低不到20%不太可能具有成本效益。
肺癌CT筛查具有成本效益的最可行情况是，如果针对极高危个体，且筛查要么非常有效，要么CT筛查成本大幅下降。
